backup-tool/app/skeleton.py

76 lines
1.8 KiB
Python

from typing import Dict
class InvalidKeyError(Exception):
def __init__(self, key):
self.message = "Invalid key: {}".format(key)
super().__init__(key)
class MissingKeyError(Exception):
def __init__(self, key):
self.message = "Missing key: {}".format(key)
super().__init__(key)
def merge(*dicts: [Dict]) -> Dict:
# Base cases
if len(dicts) == 0:
return {}
if len(dicts) == 1:
return dicts[0]
# We merge the first two dicts
d1, d2 = dicts[0], dicts[1]
output = d1.copy()
for key, value in d2.items():
if type(value) == dict:
# Merge the two sub-dictionaries
output[key] = (
merge(output[key], value)
if type(output.get(key)) == dict
else value
)
else:
output[key] = value
return merge(output, *dicts[2:])
def merge_with_skeleton(data: Dict, skel: Dict) -> Dict:
"""
Compare a dict with a given skeleton dict, and fill in default values where
needed.
"""
# First, check for illegal keys
for key in data:
if key not in skel:
raise InvalidKeyError(key)
# Then, check the default values
for key, value in skel.items():
if key not in data:
# Raise error if there's not default value
if value is None:
raise MissingKeyError(key)
# Replace with default value
data[key] = value
# Error if value is not same type as default value
elif type(data[key]) != type(value) and value is not None:
raise TypeError("Invalid value type")
# Recurse into dicts
elif type(value) == dict:
data[key] = merge_with_skeleton(data[key], value)
return data